private void NewClientButtonClick(object sender, RoutedEventArgs e)
 {
     NewCustomer newCustomerWindow = new NewCustomer();
     newCustomerWindow.CustAttr.SelectedIndex = 0;
     newCustomerWindow.Closing += newCustomerWindow_Closing;
     newCustomerWindow.editMode = false;
     newCustomerWindow.Firm.Visibility = UIResources.Visible;
     newCustomerWindow.ShowDialog();
 }
 private void EditClientButtonClick(object sender, RoutedEventArgs e)
 {
     NewCustomer newCustomerWindow = new NewCustomer();
     newCustomerWindow.Closing += newCustomerWindow_Closing;
     newCustomerWindow.editMode = true;
     newCustomerWindow.Firm.Visibility = UIResources.Hidden;
     WindowHelpers.FillNewCustomerWindow(newCustomerWindow, ComboBoxCustomer.SelectedItem as Customer);
     newCustomerWindow.ShowDialog();
 }